<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>Document</title>
  </head>

  <body>
    <div id="app"></div>
    <script>
      let number = 999
      function fn() {
        return "测试"
      }
      //   let test = "hello"
      //   let tpl = `hello world ${number}`

      //   let tpl2 = `hello world ${number-100}`
      //   console.log(tpl2)
      let tpl3 = `hello world ${fn()}`
      console.log(tpl3)
      let tpl4 = `hello
       world`
      let tpl5 = "hello" 
      + "world"
      console.log(tpl4)
      console.log(tpl5)
    </script>
  </body>
</html>
